I. Field and Purview
The present invention concerns a device for direct refrigeration of a component of a system or the entire system by which a cooling intermediary such as methanol or other liquid can be avoided and in which expansion of refrigerant in the component or system itself cools, directly, the same. Typically, heating is carried out. The foregoing can be carried out, in particular, with a solid heat-conductive block, for example, a metal block in which sample test cell(s) is(are) present such as for viscometric testing of an engine oil and so forth at a specified temperature. Among other things, the invention provides for cooling moderation so as to ameliorate or avoid perceptible cold spots in the block.
II. Art and Problems
Hildebrandt et al., U.S. patent application Ser. No. 10/077,236 filed on Feb. 15, 2002 A.D., which issued as U.S. Pat. No. 6,786,081 (Sep. 7, 2004), discloses direct and/or opposing flowpath refrigeration. In a particular case, that invention is embodied to include a block having test cells for viscometric testing of oil, which can be beneficially employed in ASTM D 4684 type testing, and supplant the Cannon Mini-Rotary Viscometer (MRV). Compare, Selby et al., U.S. Pat. No. 5,852,230.
As fine an instrument as is the device of Hildebrandt et al., it is not without its drawbacks. Chief among these are that, although laboratory safety owing to the absence of methanol and control of temperature are excellent and better than those of the MRV, in the rapidly evolving field of oil testing, where advances in data collection and interpretation follow upon instrumental precision, the temperature may vary slightly from cell to cell with a perceptible cold spot appearing, particularly about the location at which the refrigerant supply enters the block; and control of the temperature was not as symmetrical as sought, and the bar is high, with respect to a rectangular box shaped block.
It would be desirable to ameliorate or overcome the same.